| 摘要 |
<p>Electrochemical diffusion measuring cell for determining the concn. of a gas, esp. SO2 or NOx, in a fluid, esp. a liquid, has a layer of electrolyte between the measuring and reference electrodes, which are sepd. by a gas-permeable membrane. There is a diffuser, consisting of one or more layers of electrically insulating, chemically neutral fabric between the measuring electrode and the membrane. There are uniformly distributed channels for the gas through each layer of fabric. The novel features are that the electrolyte layer consists of an acid electrolyte (aq. H2SO4, HClO4 or H3PO4) and the anodic measuring electrode of (vitreous)carbon, whilst the open area of the channels through (at least one of the layers of) the fabric is max. 20 (max. 10)%. The cell has increased measuring stability for long operating periods, even at high concns. of the gas to be measured and of impurities. Pref. the diffuser is made from (polyester) monofilaments and is under 0.5 mm thick.</p> |
